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Message-ID: <tencent_BEF36CE365896CC3B36456B765576766C105@qq.com>
From: Edward Adam Davis <eadavis@qq.com>
To: syzbot+a5e651ca75fa0260acd5@syzkaller.appspotmail.com
Cc: chao@kernel.org,
	jaegeuk@kernel.org,
	linux-f2fs-devel@lists.sourceforge.net,
	linux-fsdevel@vger.kernel.org,
	linux-kernel@vger.kernel.org,
	syzkaller-bugs@googlegroups.com
Subject: [PATCH] f2fs: fix uaf in destroy_device_list
Date: Sat, 13 Jan 2024 19:28:31 +0800
In-Reply-To: <000000000000aac725060ed0b15c@google.com>
References: <000000000000aac725060ed0b15c@google.com>
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When the call to f2fs_fill_super() fails, only the memory occupied by sbi is 
released, but s_fs_info is not set to NULL, this will cause the current issue
to occur. 

Reported-and-tested-by: syzbot+a5e651ca75fa0260acd5@syzkaller.appspotmail.com
Signed-off-by: Edward Adam Davis <eadavis@qq.com>
---
 fs/f2fs/super.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/fs/f2fs/super.c b/fs/f2fs/super.c
index d00d21a8b53a..9939e2445b1e 100644
--- a/fs/f2fs/super.c
+++ b/fs/f2fs/super.c
@@ -4879,6 +4879,7 @@ static int f2fs_fill_super(struct super_block *sb, void *data, int silent)
 free_sbi:
 	if (sbi->s_chksum_driver)
 		crypto_free_shash(sbi->s_chksum_driver);
+	sb->s_fs_info = NULL;
 	kfree(sbi);
 
 	/* give only one another chance */
-- 
2.43.0